In Multiple Sclerosis, persistence of neurological symptoms is attributed to the demyelination and axonal injury. Our long term goals are to establish a scientific basis of therapies that will ameliorate the symptoms and signs that these patients. One therapeutic approach is the use of cells for transplantation to aid in the repair process. Based on our preliminary results, we hypothesize that bone marrow derived human mesenchymal stromal cell (hMSC) can differentiate into oligodendrocytes and thus may be source of cells for such therapies. The immediate goals are: Aim 1. To generate purified oligodendroglial cells from hMSCs in culture. hMSCs will be plated on surfaces that favor oligodendrocyte development and then treated with growth factors known to generate oligodendrocytes from embryonic or neural stem cells. The resulting populations of cells will be characterized to determine the proportion of cells of the oligodendrocyte, astrocyte, neuron, and microglial lineages. We will determine the effect of growth factors and culture conditions on generation of oligodendrocyte precursors so that we can maximize the numbers and survival of oligodendrocyte progenitors for transplantation. Purification methods all ready used on rat and mouse cells in our laboratory will be employed. Aim 2. To investigate the importance of -neuregulin and delta/jagged on differentiation of hMSC5 into oligodendrocyte and astrocyte lineages. The cells will be exposed GGF2 and jagged/delta and the expression of OL and astrocytic markers will be assessed by immunocytochemical methods. To confirm observations with jagged/delta, the hMSCs will be transfected with constitutively activated notch1 receptor and these cells will be studied for expression of OL and astrocytic markers. Aim 3. To investigate the feasibity of generating hMSC cell lines that retain the capacity to differentiate into OL. To generate such lines the catalytic subunit of human telomerase, v-myc and H-ras will be used to infect hMSC. After selection of cells, and determining the expression of the exogenous gene, the ability of the cell lines differentiate into OL will be tested. In all three aims, the cell culture work on OL differentiation will be supported by transplantation studies. The easy availability of sufficient number of cells or cell lines capable of differentiating into OL should be considered as a first to address the question of autologous cell transplantation as a therapeutic consideration for demyelinating/dysmyelinating diseases.